Computer-implemented geographic information systems are well known in the art and typically are configured to provide digitized maps to end-users that contain information pertaining to a wide variety of features such as lakes, rivers, roads, etc. In many instances, computer-implemented geographic information systems are configured to enable an end-user to perform searches for a particular location within a given digitized map and also to choose a scale at which the digitized map is displayed.
FIG. 1 illustrates a digitized map 100 of a portion of a county composed of individual layers of data, as is commonly found in the prior art. As shown, the digitized map 100 includes various categories of map features, such as a city 101, a lake 102, a river 103, a major road 104, a minor road 105 and a fire hydrant 106. The digitized map 100 also may include a visual scale 107 to indicate the relationship between a distance on the digitized map 100 and the actual distance. Typically, the digitized map 100 includes a different layer for each type of map feature displayed. For example, the digitized map 100 may include a layer to display various cities, such as the city 101, and another layer to display fire hydrants, such as the fire hydrant 106. To render the digitized map 100 at a particular map scale, a computer-implemented geographic information system usually superimposes the layers that are displayed at that map scale on top of one another in a predetermined order. A map-developer typically determines the order in which the layers are superimposed builds this information into the computer-implemented geographic information system. In addition, each layer also may include one or more graphics styles for representing the map feature associated with that layer at different map scale ranges or to indicate different conditions. For example, a layer for minor roads may have a first style (e.g., a thick line) for showing the minor road 105 on a zoomed-in or large-scale map and a second style (e.g., a thin line) for showing the minor road 105 on a small-scale map.
The map-developer determines the ranges of map scale at which each layer and associated graphics style(s) are displayed in the digitized map 100. For example, the map-developer may choose to show the minor road 105 only in local maps since presenting minor roadways on a small-scale map, such as a map of the entire United States, would be impractical. Conversely, showing the names of the country and state in a map of a small suburb would be inappropriate. The choices made by the map-developer regarding the map scale ranges for each layer directly affects the usability of the digitized map 100 because displaying too much detail may result in an unreadable map while displaying too little detail may render the map less useful. Further, since the time required to download the digitized map 100 to an end-user computing device directly relates to the amount of data required to generate the digitized map 100 at a particular map scale, the map-developer also needs to consider how the various data weights of the digitized map 100 at different map scales affect the navigational usability of the digitized map 100. For example, data weights that are too large may cause downloading delays if the available bandwidth to the end-user computing device is limited.
A given digitized map may include upwards of a hundred or more layers. When building such a map, the map-developer faces the difficult and tedious task of organizing and managing the data associated with all of the different layers of the map. Currently, map-developers manage the layer settings (including the associated display ranges and graphics styles) for each layer via individual dialog boxes. To globally organize all of the different layers of the map and the respective settings for those layers, however, map-developers oftentimes rely on spreadsheets or even paper and pencil. These tracking methods fail to provide an efficient visual organization of the layers of the digitized map, the ranges of map scales at which the various layers are displayed in the digitized map or the different graphics styles associated with the various layers of the digitized map. Further, these methods provide no way of sampling the digitized map to test its navigational usability.
Therefore, there is a need for a system that enables a map-developer to efficiently organize and manage the layers of a digitized map based on parameters such as the draw priority of the various layers, the graphics styles associated with each of the various layers and the ranges of map scale at which the various layers are displayed in the digitized map. Further, there is a need for a system that enables a map-developer to analyze data weights and transmission times of the digitized map at various map scales to determine the navigational usability of the digitized map.